Oxalyl diimino bis(2, 2-dimethyl acetic acid), esters and condensation polymers



OXALYL BIIMENE) BiS(2,2-l3lMETHYL AQETIC AGED), ESTERS AND CONDENSATION PGLY- ohn .R, aldwell and Cla e ce Q- Da in l y, K por Tenn, assigpors to Eastman Kodak Company, Rockies! ter, N.Y., a corporation of New Jersey as Drawing. F d oh. ,1, 195 Se No 612,987

Claims. ((11. 260,-.475)

,ELQ e eHoFNa i rm-(snowsQQB ith r ou s yee e Howev r, the pri r ar has r cognized. th t x: should e a east It a be ie ed tha when s malle t a th se compou ds nae be usefully employed to produce polymers, For ample,

which can be formed by reacting the sodium salt of glycine with diethyl oxalate as described in Ber. 30, 580 (1897 cannot be condensed with glycols to give a polymer under the conditions such as described in Example 2 set. for h b low! Attemp s to de s predueeda laek color urin the ear y ag s'o the reaction ani n polymer was obtained.

hen the examide derival Qt 4- miae b yrie ac namely,

ethnlsyedunder' the eenditieas" de cribed Example 2 set forth below, it also would not cond nse w th sl'yeels nd he a o Prod ct. we s euhd to ontain only 9 3% nitrogen screened to. the. theoretical alue 33% hich would be pected it he conden ation had taken p a In view of the prior art it would not be expected that a useful p lymer. c uld he obtained from an is m r of hat. compou d o t e general. formula g ven abo e wher t is3,

oreov the literature s ited a ove: (Ber. 30,. 580) states that a-alanine could not be reacted to form a condensation Product with d ethyl oxala e althou h y i d e It w d. appe r hat the a on wou d no proceed because the amino group in u-alanine is na secondary carbon atom.

It was therefore quite unexpected to discover that the ethyl ester of 2-amino-Z-methylpropionic acid (which is a derivative of glycine) could be condensed with diethyl oxalate to form the ethyl ester of 2,2'-oxalyldiiminobis (2,2-dimethylacetic acid).

It is an object of this invention to provide new chemical compounds which include 2,2'-oxalyldiiminobis(2,2-bismethylacetic acid) and dialkyl esters thereof.

It is another object of this invention to provide new highly polymeric condensation polymers prepared by re acting one or more of these new compounds with a dialkyl inc ester of oxalic acid, which polymers are useful for film fibers, fabric, molding compositions, coating materials and he like. 7

Other objects will become apparent hereinafter. According to a principal embodiment of this invention there is provided a compound having the formula:

wherein R represents a member selected'from the group consisting of a hydrogren atom and an alkyl radical con taining from 1 to 8 carbon atoms.

According to another embodiment of this invention there is provided a process comprising reacting, at an elevated temperature under conditions such that the alkyl alcohol being formed is evaporated, approximately two mole proportions of (3H3 rmi-p-o 0-0 R CHa together with one mole proportion of RO-(ii -i'il-O R wherein each R represents an alkyl radical containing from 1 to 8 carbon atoms so as to produce In accordance with another principal embodimentof hisiuvention there is p vided a highly polymericlinear cond ns ion p lym r 7 sub antially comprising recurring structural units having the following formula:

wherein R" represents the dehydroxylated residue of a biiune ional glycol containingfrom 2 to 12 carbon atoms (Straight or branched chain).

According to another embodiment of this invention there is provided in a process for preparing a highly polymeric linear condensation polymer by reacting a bitunct enaldicarboxy e ompound with a bifunctional: g ycol containing from 2 to 1-2 carbon atoms at an elevated: emper ture in the presence of a con en i g a e t under an inertatmosphere employing a greatly reduced pressur towardthe end of the reaction, the improvement'consisting of the: employment ofv a. lower alkyl ester of 2,2" oxalyldiiminobis 2, 2- methylacetic acid) as a; substan tial proportion of the said 'bifunctional dicarboxylic corn Pound (i cl e r ati s and. aromatics). I

The various esters referred to herein include these well knQWH alkyl esters wherein the alkyl radiGalS are generally derived from. alc hols con aining fr m 1 to 8 carbon atoms. s ch as methyl, ethyl, n-pronyl, i epropyh; .n-bu yl ertu vl tert. amy 2-ethy1h xyh t t, edyhn octyl, etc. Of course higher alcohols can be similarly employed under appropriate circumstances.

The reaction conditions contemplated in forming the monomeric starting material are similar to those described in the cited literature and involve the employment of conventional apparatus and chemical techniques readily apparent to those skilled in the art which are apropos to this type of condensation reaction wherein the volatile byproduct is removed by evaporation into a suitable condenser which efiiects its separation from the desired reaction product, e.g. see Example 1 hereinbelow. The

. have the formula depicted above.

end of the reaction can be conveniently determined by measuring the amount of byproduct which is separated, i.e. an alcohol. bviously, it is most convenient to employ an alkyl ester producing an alcohol having a boiling point at a temperature which permits the employment of simple apparatus and requires a reasonably short reaction time. Most advantageously, the ethyl esters are employed.

The employment of these monomeric starting materials in preparing condensation polymers such as polyesteramides is carried out in accordance with those well known techniques such as have been described in US 2,356,702, U.S. 2,130,523, U.S. 2,130,948, U.S. 2,245,129,

U.S. 2,500,317, U.S. 2,752,328 and many other U.S. patents. There is nothing to be gained herein by elaborating upon the conditions employed, the apparatus used orthe techniques involved since the contribution of the present invention relates to the employment of new starting materials as described herein. Examples 2 and 3 hereinbelow adequately illustrate this embodiment of the invention. Generally, at least 25 mole percent of the recurring structural units in the preferred polymers Most advantageously these recurring structural units comprise from about 25 to about 80 mole percent of the polymer.

This invention can be further illustrated by the following examples of preferred embodiments although it will be understood that these examples are included mereblends or oopolymers with other known Polymeric 1y for purposes of illustration and are not intended to limit the scope of the invention unless otherwise specifically indicated: Example 1 The following reactants were mixed together in a reaction vessel attached to a condenser: 100 g. of'the 'ethyl ester of 2-amino-2-methylpropionic acid and 55.5

4 nitrogen, as compared with a theoretical value of 3.3% N. The high viscosity and nitrogen content of the product show that the amino acid derivative was stable and remained in the polymer.

Example 3 Using the general procedure described in Example 2, a polymer was made from 2 moles of 2,2'-oxalyldiiminobis(2,2-diemthylacetic acid), 1 mole of 4,4-sulfonyldibenzoic acid, and tetramethylene glycol. The product had an inherent viscosity of 0.65 and a nitrogen content of 5.3% as compared with a theoretical value of 5.7%. 'Ihe polyester-amide softened at 230-240 C. and gave fibers that dyed well with cellulose acetate dyes, premetallized dyes, acid wool dyes, and some direct cotton dyes.

The polymers of Examples 2 and 3 were formed into films which were biaxially stretched and heat-set. These films were excellent wrapping materials, electrical infibers has been mentioned above. Oriented heat-set fibers was obtained of the diethyl ester of 2,2'-oxalyldiiminobis- (2,2-dimethyl acetic acid). This product was recrystallized from isopropyl alcohol. It had a MP. of 91.92.5 C. and elemental analysis showed nitrogen 8.77% compared. to the theoretical 8.86%. A portion of this ester was hydrolyzed employing sulfuric acid as a catalyst thereby forming the free acid.

Example 2 10 g. of dimethyl terephthalate, 7.7 g. of 2,2'-oxalyldiiminobis(2,2-dimethylacetic acid) diethyl ester, 14 g. of butanediol-1,4, and 0.01 g. titanium butoxide were placed in a vessel equipped with a stirrer, a distillation column, and an inlet for nitrogen gas. The mixture was stirred at 190-200 C. in an atmosphere of, nitrogen and a mixture of these polymers can be formed into yarns,. threads, ropes, tire cord, fabrics of the woven or unwoven types, etc. They are characterized by excellent dyeability and overall good qualities, especially when employed in terials of desirable film-forming or fiber-forming utility.

Although the invention has been described in considerable detail with reference to certain preferred embodiments thereof, it will be understood that variations and modifications can be eflt'ected without departing from the spirit and scope of the invention as described hereinabove and as defined in the appended claims.

We claim: 1. A compound having the formula:

OH] I (I) 0 CH1 RO-O Gil-NH---NH-l-C O-O R H: H: wherein R represents a member selected from the group consisting of a hydrogen atom and an allcyl radical containing from 1 to 8 carbonatoms. I

2. The diethyl ester of 2,2'-oxalyldiiminobis(2,2- dimethylacetic acid).

3. A highly polymeric linear condensation polymer of (A) a bifunctional dicarboxylic acid composed of from of methyl and ethyl alcohols was removed through the herent viscosity of 0.61 as measured in a solvent consisting of 60 cresol-40 tetrachloroethane. It contained 3.4%

25 to mole percent of 2,2'-oxalyldiiminobis(2,2sdimethylacetic acid) and (B) a bifunctional aliphate glycol containing from 2 to 12 carbon atoms.

. 4. A polymer as defined in claim 3 of (A) 2,2'-oxalyldiiminobis(2,2-dimethylacetic acid) and terephthalic acid as the bifunctional dicarboxylic acids and (B) tetramethylene glycol as the bifunctional glycol.

5. A polymer as defined in claim 3 of (A) 2,2-oxalyldiiminobis(2,2-dimethylacetic acid) and 4,4-sulfonyldibenzoic acid as the bifunctional dicarboxylic acids and (B) tetramethylene glycol as the bifunctional glycol.

References Cited in the file of this patent IkA.C.S., 75, pages 3413-17 (1953), article by South- W10 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No 2,945 OO9 July l2 1960 John R.a Caldwell et a1.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 1, line l6 for "2 2=-oxalyldiminobis(2,2 dimethylacetic acid)" read 2,2-oxalyldiiminobis(2 2 dimethylacetic acid) column 4 line 51, for "aliphate read aliphatic Signed and sealed this 4th day of April 19616 5211 ERNEST w. SWIDER XXXM ARTHUR w. CROCKER Attesting Oificer Acting Commissioner of Patents 

1. A COMPOUND HAVING THE FORMULA: 